Candles. Lanterns. Torches. Campfires. They give off beautiful light, but not very much of it. (Well, except full frame flames like that at right. And don’t be concerned - it’s not a person but a flame-test dummy dressed in a firefighter’s uniform.) But, whether the candles are on a birthday cake or the campfire is out on the prairie, that golden source of light is the point of the picture—the kid about to blow them out, the cowboys cooking their evening meal. And we’ve all had the problem, especially if we are shooting in an auto mode. If there’s not much ambient light, the flame is bright, everything else is really dark. If there’s a flash unit built into your camera, it’s going to want to go off, and its light will overpower the golden glow, even make candles look as if they are not lit. Instead of a warm glow you get a harshly lit, overly bright scene. So what do you do to make the flames visible and capture that mood you are after?
Slow Shutter Speed:
The main trick is to use a slow shutter speed. Any light, whether it’s a source or reflected, needs time to record itself on your sensor—the brighter the light, the less the time; dim light needs lots of time. And the size of the aperture matters too. Small holes (f16, f22, etc) let in little light; big holes (f2, f2.8. etc.) let in a lot. It takes some experimentation to get the right shutter speed/f-stop combination because of the variables—a pressure lantern is brighter than a kerosene one, which is brighter than a candle; how far away from the light source is your subject? A good rule of thumb for birthday candles is to start at 1/15th of a second at f 5.6. (It’s good to use a mid-range f-stop so you have some depth of field—see the “Sharp or Fuzzy” Tips Flick and Actual Info for more on depth of field.) One of the many great things about digital cameras is that you can immediately check to see if your exposure works. If it doesn’t, try a slower shutter speed or larger aperture—but don’t go too slow with the shutter speed or the kid blowing out the candles will get blurry.
If you are making images of someone sitting by a campfire, you can be pretty sure that the light will be fairly constant. But if you’re shooting someone blowing out candles on a cake, remember that the amount of light is going to decrease rapidly, and then there will be none. One of the few advantages of getting older is that you get more candles—and more light. And it takes longer to blow them out, so you can fire off more pix.
Modern flash units and the flashes built into most cameras have adjustable outputs—that means that you can tell the flash to put out more or less light than it normally would in a given situation. The adjustment can be made in one of the menus under “Flash Level” or something similar, is usually in increments of 1/3, and can go to as little as -3 stops or +3 stops. I shot all the images of our friendly flamingo (below) at 1/8th second at f 5.6. In the first row, you can see how rapidly the light falls off as he moved away from the candle.
In these images, I used the flash at its full power—too much for my taste. There’s no mood to the pictures.
In these images I adjusted the flash to -3. You can see that there is more detail in the flamingo in all the shots. But except for the one where he (I’m assuming it’s a he) is near the candle, you lose the effect of the flame. But you can see him, which you can just barely do when he’s far away with no flash.
Here’s how it works: In the middle row, the flash did some calculations and put out enough light to properly expose the subject for the shutter speed/aperture setting it read from the camera—1/8th second at f 5.6. That’s what full-on flash does. In the bottom row, I told it to put out three stops less light. Again, the flash did some calculations and then put out light for a proper exposure at 1/8th second at f 16. That’s not a lot of light, but enough to give us detail without overpowering the flame.
Here’s a closer look when he’s near the flame:
Getting this right takes some practice – slow enough shutter speed to show the flame(s) but fast enough to freeze your subject (unless you want blur). To get it, you may need to increase the ISO setting on the camera – the newer models make amazing pictures at high ISO ratings, with little “noise,” or what we called “grain” in the film days. So experiment a lot, figure out what works in different situations, and fire away!
Actual Info: Text ©2010 Robert Caputo
Photos © 2010 Cary Wolinsky, © 2010 Robert Caputo